Linux: >> Linux Kernel >> 6.6.49 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
iavf: get rid of the crit lock
Get rid of the crit lock.
That frees us from the error prone logic of try_locks.
Thanks to netdev_lock() by Jakub it is now easy, and in most cases we were
protected by it already - replace crit lock by netdev lock when it was not
the case.
Lockdep reports that we should cancel the work under crit_lock [splat1],
and that was the scheme we have mostly followed since [1] by Slawomir.
But when that is done we still got into deadlocks [splat2]. So instead
we should look at the bigger problem, namely "weird locking/scheduling"
of the iavf. The first step to fix that is to remove the crit lock.
I will followup with a -next series that simplifies scheduling/tasks.
Cancel the work without netdev lock (weird unlock+lock scheme),
to fix the [splat2] (which would be totally ugly if we would kept
the crit lock).
Extend protected part of iavf_watchdog_task() to include scheduling
more work.
Note that the removed comment in iavf_reset_task() was misplaced,
it belonged to inside of the removed if condition, so it's gone now.
[splat1] - w/o this patch - The deadlock during VF removal:
WARNING: possible circular locking dependency detected
sh/3825 is trying to acquire lock:
((work_completion)(&(&adapter->watchdog_task)->work)){+.+.}-{0:0}, at: start_flush_work+0x1a1/0x470
but task is already holding lock:
(&adapter->crit_lock){+.+.}-{4:4}, at: iavf_remove+0xd1/0x690 [iavf]
which lock already depends on the new lock.
[splat2] - when cancelling work under crit lock, w/o this series,
see [2] for the band aid attempt
WARNING: possible circular locking dependency detected
sh/3550 is trying to acquire lock:
((wq_completion)iavf){+.+.}-{0:0}, at: touch_wq_lockdep_map+0x26/0x90
but task is already holding lock:
(&dev->lock){+.+.}-{4:4}, at: iavf_remove+0xa6/0x6e0 [iavf]
which lock already depends on the new lock.
[1] fc2e6b3b132a ("iavf: Rework mutexes for better synchronisation")
[2] https://github.com/pkitszel/linux/commit/52dddbfc2bb60294083f5711a158a
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod()
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: fix double-free on mc_dev
The blamed commit tried to simplify how the deallocations are done but,
in the process, introduced a double-free on the mc_dev variable.
In case the MC device is a DPRC, a new mc_bus is allocated and the
mc_dev variable is just a reference to one of its fields. In this
circumstance, on the error path only the mc_bus should be freed.
This commit introduces back the following checkpatch warning which is a
false-positive.
WARNING: kfree(NULL) is safe and this check is probably not required
+ if (mc_bus)
+ kfree(mc_bus);
CVSS Score
7.8
EPSS Score
0.001
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pp: Fix potential NULL pointer dereference in atomctrl_initialize_mc_reg_table
The function atomctrl_initialize_mc_reg_table() and
atomctrl_initialize_mc_reg_table_v2_2() does not check the return
value of smu_atom_get_data_table(). If smu_atom_get_data_table()
fails to retrieve vram_info, it returns NULL which is later
dereferenced.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: eir: Fix possible crashes on eir_create_adv_data
eir_create_adv_data may attempt to add EIR_FLAGS and EIR_TX_POWER
without checking if that would fit.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Fix NULL pointer deference on eir_get_service_data
The len parameter is considered optional so it can be NULL so it cannot
be used for skipping to next entry of EIR_SERVICE_DATA.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
ptp: remove ptp->n_vclocks check logic in ptp_vclock_in_use()
There is no disagreement that we should check both ptp->is_virtual_clock
and ptp->n_vclocks to check if the ptp virtual clock is in use.
However, when we acquire ptp->n_vclocks_mux to read ptp->n_vclocks in
ptp_vclock_in_use(), we observe a recursive lock in the call trace
starting from n_vclocks_store().
============================================
WARNING: possible recursive locking detected
6.15.0-rc6 #1 Not tainted
--------------------------------------------
syz.0.1540/13807 is trying to acquire lock:
ffff888035a24868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at:
ptp_vclock_in_use drivers/ptp/ptp_private.h:103 [inline]
ffff888035a24868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at:
ptp_clock_unregister+0x21/0x250 drivers/ptp/ptp_clock.c:415
but task is already holding lock:
ffff888030704868 (&ptp->n_vclocks_mux){+.+.}-{4:4}, at:
n_vclocks_store+0xf1/0x6d0 drivers/ptp/ptp_sysfs.c:215
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&ptp->n_vclocks_mux);
lock(&ptp->n_vclocks_mux);
*** DEADLOCK ***
....
============================================
The best way to solve this is to remove the logic that checks
ptp->n_vclocks in ptp_vclock_in_use().
The reason why this is appropriate is that any path that uses
ptp->n_vclocks must unconditionally check if ptp->n_vclocks is greater
than 0 before unregistering vclocks, and all functions are already
written this way. And in the function that uses ptp->n_vclocks, we
already get ptp->n_vclocks_mux before unregistering vclocks.
Therefore, we need to remove the redundant check for ptp->n_vclocks in
ptp_vclock_in_use() to prevent recursive locking.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
ASoC: Intel: avs: Verify content returned by parse_int_array()
The first element of the returned array stores its length. If it is 0,
any manipulation beyond the element at index 0 ends with null-ptr-deref.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
seg6: Fix validation of nexthop addresses
The kernel currently validates that the length of the provided nexthop
address does not exceed the specified length. This can lead to the
kernel reading uninitialized memory if user space provided a shorter
length than the specified one.
Fix by validating that the provided length exactly matches the specified
one.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
EDAC/skx_common: Fix general protection fault
After loading i10nm_edac (which automatically loads skx_edac_common), if
unload only i10nm_edac, then reload it and perform error injection testing,
a general protection fault may occur:
mce: [Hardware Error]: Machine check events logged
Oops: general protection fault ...
...
Workqueue: events mce_gen_pool_process
RIP: 0010:string+0x53/0xe0
...
Call Trace:
<TASK>
? die_addr+0x37/0x90
? exc_general_protection+0x1e7/0x3f0
? asm_exc_general_protection+0x26/0x30
? string+0x53/0xe0
vsnprintf+0x23e/0x4c0
snprintf+0x4d/0x70
skx_adxl_decode+0x16a/0x330 [skx_edac_common]
skx_mce_check_error.part.0+0xf8/0x220 [skx_edac_common]
skx_mce_check_error+0x17/0x20 [skx_edac_common]
...
The issue arose was because the variable 'adxl_component_count' (inside
skx_edac_common), which counts the ADXL components, was not reset. During
the reloading of i10nm_edac, the count was incremented by the actual number
of ADXL components again, resulting in a count that was double the real
number of ADXL components. This led to an out-of-bounds reference to the
ADXL component array, causing the general protection fault above.
Fix this issue by resetting the 'adxl_component_count' in adxl_put(),
which is called during the unloading of {skx,i10nm}_edac.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-07-10